Rotavirus
Adenovirus
Calicivirus
Picornavirus
Virus-virus yang ditemukan di traktus gastrointestinal
Ò Rotaviruses
Ò Adenoviruses 40/41
Ò Caliciviruses
Ò Norwalk like viruses or SRSV (Small Round Structured Viruses)
Ò Astroviruses
Ò SRV (Small Round Viruses)
Ò Coronaviruses
Ò TorovirusesROTAVIRUS
Family Reoviridae
Genus Rotavirus
Other genera Orthreovirus, Coltivirus, orbivirus (sheep)
EM identification from duodenal biopsies from children with diarrhea.
"Virus particles in epithelial cells of duodenal mucosa from children with acute non-bacterial gastroenteritis," Lancet, 1:1281-3, 1973
•Structure
–Naked double shell capsid
–11 segment double stranded RNA genome
•Pathogenesis
–Fecal oral transmission
–Replication in cytoplasm
–Fever, vomiting, diarrhea in infants and young children
–Incubation period less than 48 hr, highly infectious
–Infection of intestinal epithelium causes loss of electrolytes and prevents readsorption of water
–Long term immunity; asymptomatic infection in adults
•Diagnosis
–viral antigen detection
•Treatment/prevention
–RotaTeq live, oral vaccine
ADENOVIRUS
ÒIsolated 1953 by Rowe from adenoidal tissue
ÒLinear double-stranded DNA
Ò70-75nm in diameter
ÒGenus: Mammalian AV (mastadenoviruses)
É6 human subgenera (A-F)
É51 human serotypes (1-51)
ÒKnown oncogenic potential of some serotypes
ÒCommonly used as vectors in
gene therapy and vaccine delivery
ÒIncubation period 3 -10 days
ÒDiarrhea lasts for 10 -14 days
ÒCan also cause intussusception, mesenteric adenitis, appendicitis
ÒTreatment with cidofovir promising for severe disease in immunocompromised
•Family Caliciviridae
•Non-enveloped RNA viruses
with ss [+] sense RNA
•27-35 nm in size
•Contains single capsid protein
Morphology typical :
•32 cup-like depressions
• EM appearance of “Star of David”
• 31-35 nm size
E.g.- Sapporo-like viruses Morphology A-typical
•Smaller size- approx. 27 nm
• Rough, feathery surface but no internal pattern
• Small Round Structured viruses
E.g.- Norwalk-like viruses SPREAD
ÒPerson-to-person fecal-oral spread (stool/vomitus)
ÒFecal contamination of food or water
ÒFomites (stool/vomitus)
ÒIngestion of aerosolized particles
SPREAD-VIABILITY
ÒSurvive on surfaces for several days
ÒSurvive in water chlorinated at routine levels (up to 10 ppm)
ÒSurvive freezing, heating up to 60°C
ÒEvidently survive in steamed shellfish
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